While Mona was missing in last week’s episode of Pretty Little Liars - off competing in the Academic Decathlon - look for the devious A-Team member to return tonight and get right back to her favorite pastime: driving Spencer insane.

Janel Parrish jumped on the phone with us yesterday to preview the installment episode. And, according to the actress, Spencer is going to continue to spiral out of control with more than a little help from Mona. Read More...